Spin transport and wavevector-dependent spin filtering through magnetic graphene superlattice

We investigate the spin transport properties of magnetic graphene superlattice in the presence of Rashba spin–orbit interaction (RSOI). We consider two types of magnetic profiles: a sequence of N square magnetic barriers and a sequence of delta magnetic barriers. In the first case it is found that the angular range of the spin transmission through magnetic graphene superlattice can be efficiently controlled by the number of barriers and this renders the structureʹs efficient wavevector-dependent spin filters. As the number of magnetic barriers increases, the angular range of the spin transmission decreases, the gaps in transmission and conductivity versus energy become wider. In the second case, when the magnetic field is present, the spin polarization increase with increasing the magnetic field. In both cases, the magnetoresistance ratio shows a strong dependence on the number of magnetic barriers.